FTP change for NCAR supercomputers

New network security filters have been installed that affect NCAR's supercomputing systems. It is no longer allowed to use FTP to transfer files while on the supercomputers (only sftp is permitted). However, there is an ftp proxy available from the supercomputers.

Using the FTP proxy from an NCAR supercomputer

The following procedure shows how to use FTP when you are logged on to an NCAR supercomputing system: you FTP to the roy-s system and log in using your user_id and the domain name for the remote host. Then if your account on the remote host requires a password, you supply that password.

Interactive use

When you are logged on to an NCAR supercomputer, and you want to FTP to a remote host, type:

   ftp roy-s

The gatekeeper system will respond like this:

   Connected to roy-s.ucar.edu.
   220 abby.ucar.edu FTP proxy (Version V1.3) ready.
   Name (roy-s:user_id):

At the Name prompt, type:

   user_id@remote_host

This connects you to your desired site. If you are prompted for a password, use your password for the remote host. Examples:

Name (roy-s.ucar.edu:user_id): anonymous@ftp.ncep.noaa.gov
Name (roy-s.ucar.edu:user_id): john_doe@cs.umich.edu
Password: ********

You can then perform all your normal FTP operations (get, put, ls, etc.), and the NCAR security filters will not affect your file transfers.

Using FTP from meeker

If you are logged on meeker, you can use the ftp proxy on the NCAR gateway computer, gate.ucar.edu. Use the same method as shown above for roy-s and the supercomputer. For example:

   ftp gate.ucar.edu

Batch use

It is preferable to store output from your jobs on the Mass Storage System. We do not generally recommend using FTP from within batch jobs because it can hang. It also risks exposing login and password information to other users and is therefore also ill-advised from a security standpoint in production batch jobs. However, if you need to FTP a file to your home computer, you can use the FTP proxy. For example, you would use the following method in your supercomputer shell script:

ftp -n -v roy-s << 'EOF'
    user jsmith@rapunzel.noaa.gov rapunzel_password_here
    cd some_directory
    put ${pgmname}.lst
    put ${pgmname}.out
    quit
'EOF'

Help

If you have any questions or problems, please contact the SCD Consulting Office by sending email to consult1@ucar.edu or by calling 303-497-1278.

Last update: 6/14/04

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Maintained by: consult1@ncar.ucar.edu
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